I recently added a fluorescent light to a circuit and it’s too dark to tell if it’s working. Now what?
I followed basic steps. There was a passel of lights already wired in parallel. I cut into one of the NM cables, added a junction box and came out to the new fixture, pigtailed it in, then came back to the junction box. I used the same gauge wire and made sure the new box and fixture were grounded. Both the original fixtures and the new fluorescent fixture works fine (hooray!). Now what?
I’m asking if there is anything else I should be doing, kind of an “am I done?” question. After adding receptacles I plug in a tester to check that everything went well. Is there anything similar with lighting circuits? I can’t think of anything or how it would work, but searching on my own is like proving a negative. Plus, all results are telling me how to test a non-functioning circuit. It’s working—I just want to know if it will burn down the house.
if you pick it up and it’s not heavy then it’s a light circuit.
the quality of wiring and the safety of the fixture can be found by inspection and experience to what wiring/fixture should look like before the circuit is energized. after it is energized you shouldn’t see sparks, hear loud sounds, feel large amounts of heat (all depends on what type and size of light).
However, the thing with beginners doing their own electrical work is that very small details can be overlooked due to inexperience. Loose wirenuts, reverse polarity, crappy grounding, etc just to name a few. It’s hard to tell from a written description just how well you’ve executed the installation. Also, the manner in which the nm cable is connected (secured) to the box and the fasteners used to mount the fixture can be other variables. Sometimes when I install light fixtures I scrap the crappy mounting hardware that came with the fixture and use more robust hardware. That actually happens quite often these days.
Thanks. So that’s it then. I’d wiggled and pulled on the ground screws and pigtails to be sure everything was tight, but haven’t the experience to tell what is and isn’t a crappy connection. The NM is held with a basic coupler, not too tight but it feels secure. It’s terribly unsettling to switch over to bare wire when I enter conduit and have nothing securing it, but that’s a different thread.
In terms of reversed polarity, that would be cross-connecting the wires, right? If I did that, the whole thing wouldn’t light, would it?
It will probably light. The problem you could have is that you might energize parts of the fixture that shouldn’t be energized, which could represent a shock hazard. This is more common in incandescent fixtures, where the shell where the bulb screws in can become energized. There is normally a chunk of insulating material between the shell and the fixture casing to prevent that sort of accident. Can’t say what would happen with a fluorescent fixture as I can’t ever recall incorrectly wiring one in the past 45 years.
I’m assuming that by “coupler” you’re referring to wire nuts? Many people twist the wires together before using a wire nut, just to make sure there is a tight connection. If you’re using some other method, like a connection block or a crimp connector, a tug on the wire will normally tell you if it’s a good connection.
Oops, I meant to type “connector,” not “coupler” (example). When my wires needed to head down the basement wall, I went from NM to bare wire. I stripped off the NM jacket and the bare wires weren’t marked at all, so trying to follow things to the letter I picked up lengths of listed bare wire and connected them inside a junction box. The connector holds the NM in the junction box (and in the fixtures where NM enters those), I left a length of bare wire in the box to make future changes easier (but didn’t crowd it), and then the bare wire wends through the EMT–with nothing in particular securing it. I think I get why that’s the case, but can’t help but feel weird about it.
individual wires in conduit is fine. conduit supports the wire and holds it secure (for longer than lengths of a few inches you need to apply significant force to get the wire to move).
in any junction box or fixture there should be no wires pulled taught and you should have 6 inches of free loose wire to work with in making connections.
bare wire would refer to uninsulated wire as in a grounding conductor. individual insulated wires are just that and shouldn’t be referred to as bare wires.
You should wrap electrical tape around the marettes (wire nuts). This is code in some areas.
If the plastic cap were to separate from the copper insert, the tape would prevent it from falling off, exposing the bare wire, causing a short, fire, etc… This could be caused by faulty manufacturing, being over-tightened on installation, or by the expansion/contraction of the copper over time.
The tape will also help prevent moisture from entering the connection, causing corrosion or shorts.
Can’t tell you how much I hate this practice; it’s actually code in some locales? Not trying to start a fight, by the way. It’s just personal preference.
Rhythmdvl: That’s what electricians usually call a Romex connector (although Romex is a brand name), which differentiates it from a flex connector, conduit connector, watertight connector or other box connector. There’s no such thing as a Romex or NM coupling that I’m aware of. Couplings are for conduits and raceways.
I personally don’t like the practice and prefer workmanship to crutches. Wrapping tape around a wire nut is a crutch, IMO, that can lead to sloppy workmanship. Note that I said “can” before anybody starts yelling. If wires are properly stripped and twisted, the wire nut will stay put, if properly sized and properly applied. If it makes you feel better about things, or if code requires it (a big rolleyes for me), then wrap tape around it. Personally, I’m confident that the splices I make are solid.
Using a multimeter*, set to resistance (200 ohms is good):
Open the breaker, and/or at minimum, turn off the light switch - I recommend both for safety
open the newly installed light and remove the connectors (you don’t have to untwist or disconnect the wires)
touch one lead to the hot leg(black or red depending on wiring)
touch the other lead to the ground wire (bare)
you should get infinite resistance [infinity symbol] showing no shorts or bleeds (open circuit)
repeat same with the neutral (white) and hot (black or red), looking for same results
This tests the wiring after the light switch, nothing prior to it.
If you get a non-infinite reading, then you may have nicked insulation or have a loose connector. Check and tighten any loose connectors and inspect all wires that are not within the outer sheath. Electrical tape over a nick in the insulation is acceptable in most cases.
testing neutral and ground will give a resistance reading, as they bypass the switch and are connected together at the panel, so it is not applicable for this test.
reasonable cost at home depot or lowes, depending on your preference - and good for everything in a standard residential home
testing a fixture with a meter will give results with an all depends. if you are testing for a short circuit and you have a bulb in place or a fixture with a transformer then you won’t get infinite resistance and the circuit could be perfectly fine.
this is definitely where skill and experience come in.
you have to know what a good connection looks like and feels like.
in addition to making good connections is properly closing up the box/enclosure/fixture. what might appear to be a good connection to an inexperienced person can become a bad connection when placed in the box/enclosure/fixture and closed if not done right.
Who cares whether you “don’t like the practice”?
You’ve obviously missed the point. There are very practical reasons to use electrical tape and this is one of them. It has nothing to do with holding the copper wires together, it’s to ensure that the plastic cap does not come off exposing the connection. It’s not about workmanship or how confident you are about your slices. It’s about the plastic cap deteriorating or separates from it’s copper insert after years of expansion and contraction of the metal.
Secondly, it’s not a “what-if” situation, it happens…often. I have seen it on many, many projects. In fact, all the licensed electricians I work with in the field employ this technique (as well as taping outlets and switches, to prevent shorts of terminal screws to the sides of electrical boxes).
I will clarify for you that you don’t mummify the connection or wrap the wires together in a bundle, you simply wrap the tape a couple of times around where the plactic and wire insulation meets.
I’m not yelling, but this kind of “Meh… I’m confident and that’s good enough for me” is what causes shocks, electrical fires, and possible deaths.
I mean come on, the <5 seconds it takes to wrap some electrical tape around plastic cap (or to take it off when required) is not a major inconvenience and prevents a potential hazard in the future. How can anyone argue otherwise?
Electrical tape also degrades, especially the cheaper stuff. Even Scotch 88 or 33 can become ineffective over time. It can become brittle and useless when old, lose its adhesive properties, or become a sticky mess in hot locations. I see no advantage to using it in this application. I think it’s delusional to think you’re gaining any advantage by doing so.
Again, it doesn’t really matter what you “see” or “think is delusional”.
I provided advice as to the practice used by those working in the trade, take it or leave it.
